Roseen, 69, alleges ISP Trooper Justin Klitch pulled him over at a rest stop as he crossed into Idaho from Washington state in January 2013, detained him for hours and searched his vehicle for marijuana for no other reason than because he had a Colorado license plate and a Washington state driver's license. Both states have legalized marijuana.

Mark Coonts, an attorney for Roseen, had no comment on the state's filing.

Roseen's lawsuit charges numerous violations of his constitutional rights, along with discriminatory and selective treatment by profiling.

The 11th Amendment to the U.S. Constitution grants states sovereign immunity from being sued for money damages.

The amendment is "a restriction on lawsuits that try to tap into the state treasury. It extends to not only the state of Idaho, but to state entities like the ISP," said Rich Seamon, University of Idaho law professor and associate dean.

However, he said lawsuits that charge constitutional violations by police and agencies generally go forward.

Lawyers for Fruitland police and the Payette county sheriff's department and their officers also have asked the court to dismiss Roseen's lawsuit against the agencies "on the basis that neither is an entity subject to suit."

Roseen's lawsuit names the officers both in their individual and official capacities, meaning if the sovereign immunity argument is successful, the lawsuit still could continue against the individual officers, Seamon said.